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改进的QuEChERS-气相色谱-质谱联用法测定蔬菜中的氟吗啉和烯酰吗啉残留 总被引:1,自引:0,他引:1
建立了同时测定蔬菜中氟吗啉和烯酰吗啉残留的改进的QuEChERS-气相色谱-质谱(GC-MS)联用法。前处理过程以乙腈高速匀浆提取样品,应用改进的QuEChERS方法对样品进行提取、盐析和净化,并采用气相色谱-质谱联用仪在选择离子监测(SIM)模式下测定了多种蔬菜中的氟吗啉和烯酰吗啉残留量,以基质匹配标准溶液外标法定量。选用DB-5 MS石英毛细管柱(30 m×0.25 mm×0.25μm),流速1.1 mL/min,采用电子轰击电离源,选择监测离子氟吗啉为m/z 285、371、165;烯酰吗啉为m/z 301、387、165。结果表明:在优化条件下,氟吗啉和烯酰吗啉在10~1000μg/kg范围内线性关系良好,相关系数不低于0.999,不同基质中的检出限(S/N=3)范围为0.67~2.42μg/kg。对于生姜、番茄、胡萝卜、菠菜、甘蓝和白木耳空白样品,在10、20、100μg/kg共3个水平下氟吗啉和烯酰吗啉的加标回收率为71%~116%,相对标准偏差(RSD)为1.8%~14.7%。同时,本研究对蔬菜中氟吗啉和烯酰吗啉残留检测的裂解机理和基质效应进行了考察。本方法具有操作简便、快速、准确的特点,可用于蔬菜中氟吗啉和烯酰吗啉残留量的日常检测。 相似文献
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Residual dynamic and risk assessment of dimethomorph in Swiss chard grown at two different sites 下载免费PDF全文
《Biomedical chromatography : BMC》2018,32(2)
Residue analysis of dimethomorph in Swiss chard cultivated at two different locations under greenhouse conditions was conducted using high‐performance liquid chromatography–ultraviolet detection and confirmed by tandem mass spectrometry. The randomly collected samples (over 14 days) were extracted with acetonitrile and purified using a Florisil solid‐phase extraction cartridge. Linearity over a concentration range of 0.05–50.0 mg/L had an excellent coefficient of determination of 0.9996. Recovery rate ranged from 82.98 to 95.43% with relative standard deviations ≤5.12% and limits of detection and quantification of 0.003 and 0.01 mg/kg, respectively. The initial deposits [day 0 (2 h post‐application)] were considerably lower (7.57 and 8.55 mg/kg for sites 1 and 2, respectively) than the maximum residue limit (30 mg/kg) set by the Korean Ministry of Food and Drug Safety. The dissipation half‐life was approximately the same, being 5.0 and 5.1 days for sites 1 and 2, respectively. Risk assessment estimated as acceptable daily intake revealed a value of 0.084 or 0.094% (day 0) and 0.014% (10 days post‐application), for sites 1 and 2, respectively. The values indicated that dimethomorph can be safely used on Swiss chard, with no hazardous effects expected for Korean consumers. 相似文献
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